The same motif can be found on the tsuba of Hanwei´s Three Monkeys Katana (Product No. SH2329).

The three wise monkeys are a widely known imagery. Together they embody the proverbial principle
"see no evil, hear no evil, speak no evil". The three monkeys are Mizaru, covering his eyes, who sees no evil, Kikazaru,
covering his ears, who hears no evil and Iwazaru, covering his mouth, who speaks no evil.